This invention relates to coating compositions which are applied to a surface, such as a floor, metal, plastic, glass or wood surface, and dry as a substantially clear, protective film.
Aqueous base coating compositions which dry to form a substantially clear and colorless protective film on the surface of the substrate to which they are applied are widely used, particularly as polishes for resilient flooring, decorative clear coatings for metals, plastics, glass or wood. Various compositions are marketed for stripping or removing the film after dirt or staining materials have become embedded in the film or prior to use or further processing of the article. These compositions typically are aqueous dispersions or are diluted in water and disrupt the film so it can be conveniently removed. When these compositions are applied to the surface, the entire surface becomes wet and one frequently cannot readily observe whether the film has been completely removed until the surface becomes dry. After drying, the non-uniform removal of the film becomes apparent and reapplication of the stripper is required. In use, up to as many as three applications of the stripper composition may be required to completely remove the film.
The problem of "missed spots" during stripping becomes acute if a metal piece is to be plated, as interference with even deposition of the plating causes rejects.
Some manufactured goods such as pots and pans can be protected against scratching during shipment and while on display with an easily removed clear, glossy protective coating. Normal use directions included with such utensils usually specify washing the utensil with warm soapy water prior to use. If the protective coating turns color, it can be easily observed when all of the coating has been removed.